Hemostasis cannula

Abstract

A hemostasis cannula includes a main body defining a passage therethrough adapted to receive a catheter. The main body has externally threaded surfaces adjacent the ends of the body to receive a cap and an end retainer threaded thereon. The cap is an open-ended cap with an opening in the top of the cap to receive the catheter. Clamped between the cap and the main body is a flexible, resilient disk-like gasket. The gasket includes an upper elongated slit extending diametrically across the top surface of the gasket and extending through the outer perimetrical edge surface of the gasket. A lower elongated slit extends diametrically across the lower surface and through the outer perimetrical surface. Both slits are cut into the gasket to a predetermined depth without passing entirely through the thickness of the gasket. In one embodiment illustrated, the slits are arranged to intersect within the interior of the gasket to provide an opening for insertion of the catheter. In another embodiment illustrated, the slits do not intersect each other, but instead have collective depths less than the thickness of the gasket. A generally axial opening is provided between the two slits. A flexible tube is affixed to the main body of the cannula by the end retainer. The flexible tube is constructed to include an inner tube with a coil body surrounding the inner tube substantially along the length of the tube. A sheath surrounds the coil body. The flexible tube thus configured resists crimping, kinking and buckling when the tube is subject to bending. The hemostasis cannula and particularly the gasket provides a leak-proof seal to prevent the flow of blood from or air into a blood vessel.